Twenty-two-year-old Jeffrey Napier plead guilty to the murders Friday in Marengo County.
Fifty-two-year-old Ida Little and her three-year-old granddaughter, Mikayla, were found shot to death inside their Linden home last August.
Mikayla's father, 42-year-old Michael Landrum, has also been charged in the case. He's expected to go to trial in October.
Meanwhile, Napier, who’s said to have been the gunman, could be sentenced in June. He faces the death penalty.